A method of downhole operations and surface well logging data acquisition

Abstract

This invention belongs to the field of mine detection technology and discloses a method for acquiring downhole and surface logging data. The steps of this data acquisition method are as follows: S1, preparation; S2, obtaining or collecting rock cuttings; S3, rock cuttings sample analysis; S4, generating downhole wired data; S5, data processing; S6, data calculation; S7, obtaining data from the analysis results. This invention overcomes the problems of wired tools being unable to operate or difficult to operate, and being costly, as well as the shortcomings and defects that wired tools may have when performing formation analysis. The advantage of this method is that when dealing with unconventional formations, in addition to generating data similar to that of downhole wired tools, it also provides formation-related rock physical parameters and data, acquiring more elemental and mineral information than traditional wired elemental logging, further expanding the scope of mineral identification. Furthermore, due to the flexibility of the method, most XRF equipment can meet the requirements.

Description

Technical Field

[0001] This invention belongs to the field of mine detection technology, specifically a method for acquiring well logging data in underground operations and on the surface. Background Technology

[0002] Drilling technology is the cornerstone of many applications deep within the Earth, such as carbon dioxide sequestration, hydrogen storage, geothermal production, and the exploration and production of hydrocarbons. In performing these tasks, boreholes need to access and may contain various substances, such as gases or fluids, below the Earth's surface. Different types of tools and instruments are placed in the boreholes to perform various tasks and measurements.

[0003] However, a challenge in drilling operations is the collection and processing of data related to the downhole formation and its properties (such as rock petrology). Typically, wireline tools running through the borehole are used for formation analysis, such as rock properties and petrology. But in certain formations, such as soft, weak unconventional shale and high-pressure, high-temperature formations, data collection becomes particularly difficult. In these formations, due to their relative weakness, placing wired tools into the drilled hole can be difficult, and doing so carries a high risk of borehole damage or collapse. Furthermore, these soft / hazardous unconventional formations can complicate drilling operations, as relying solely on surface data collection and analysis may be insufficient for real-time field decision-making. Therefore, a more effective approach to downhole operations and surface logging data acquisition is needed. Summary of the Invention

[0004] The purpose of this invention is to provide a method for acquiring downhole and surface logging data to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for acquiring downhole and surface logging data, the steps of which are as follows:

[0006] S1, Preparatory work; Based on geological exploration data and the geological structure of the target area, determine the drilling location, drilling depth, and drilling type for downhole operations;

[0007] S2, Obtaining or collecting cuttings; cuttings can be obtained or collected at the surface location during drilling operations, through the drilling fluid circulated by the drilling pump during the drilling process.

[0008] S3, Cuttings Sample Analysis; Cuttings sample analysis is performed using a single XRF-based surface tool or a combination of XRF and XRD-based surface tools, producing two sets of cuttings analysis data;

[0009] S4 generates downhole wired data; downhole wired data is generated by simulating the cuttings analysis data obtained in S2.

[0010] S5, Data Processing: Process the generated raw data, such as filtering, denoising, and correction, to obtain well logging curves that can be used for analysis;

[0011] S6, Data Calculation: Use the data obtained above as different inputs into the formula, and obtain the corresponding output as the result based on the input;

[0012] S7, Analyze the results to obtain data; analyze the obtained data and acquire downhole operation and surface logging data.

[0013] Preferably, the rock fragmentation analysis data in S3 is specifically an elemental or mineral dataset. The physical data of these rock fragments are obtained based on the elemental or mineral datasets of XRF and XRD data, specifically including: density, rock strength, and sound wave propagation time.

[0014] Preferably, the formula used in S6 is: ((mineral A * coefficient + mineral B * coefficient + ...) * adjustment coefficient) / adjustment coefficient;

[0015] Specifically

[0016] Wherein GR represents the gamma output of the cuttings, U% is the percentage of uranium in the sample, Ur is the elemental radiation of uranium in the sample, Th% is the percentage of thorium in the sample, Thr is the elemental radiation of thorium in the sample, K% is the percentage of potassium in the sample, and Kr is the elemental radiation of potassium in the sample; furthermore, in the equation, A, B, and C are coefficients used to determine the gamma values ​​from the cuttings data; coefficients A, B, and C are derived from the correlation of the core data.

[0017] Preferably, the density of the rock fragment mineral matrix involved in S6 is:

[0018]

[0019] Where ρcutting is the density of the rock fragment mineral matrix, M1 is the amount of the first mineral in the sample, ρ1 is the density of the first mineral, M2 is the amount of the second mineral in the sample, ρ2 is the density of the second mineral, M3 is the amount of the third mineral in the sample, ρ3 is the density of the third mineral, Mn is the amount of the nth mineral in the sample, and ρn is the density of the nth mineral.

[0020] Preferably, the relationship between the rock fragment mineral matrix density and the DTC from the cross-dipole pair involved in S6 is as follows:

[0021] DTC 岩屑 =1*(1-DTC) index2 )*ρ cutting *DTC index3 +DTC index1

[0022] Where DCTbulk is the volumetric DCT, ρcutting is the fifth output mineral matrix density of cuttings (calibrated with core), DCTindex1, DCTindex3 and DCTindex4 can be obtained from the cross-dipole logarithmic correlation model, and the density is also obtained from the cross-dipole wired logging. Then, the relationship between density and DTC is established using the cross-dipole wired logarithmics, and the DTC algorithm is established using the cross-dipole wired logarithmics. Based on the density of minerals as the input of the algorithm, DTC is generated. The mineral matrix DTC is a pseudo-value and must be calibrated with cores.

[0023] Preferably, the well diameter involved in S6 is:

[0024]

[0025] Where Cindex is the borehole diameter index, ρcutting is the density of rock cuttings mineral matrix, and B is brittleness. The borehole diameter index, as an indicator of borehole shape, represents the original borehole shape without reaming or reaming. Reaming and reaming drilling operations may alter the original shape. Here, the borehole diameter conforms to the original borehole shape. The borehole shape is determined by the rock strength; the harder the rock, the more complete the borehole shape. Density plays an important role in rock strength, having a positive correlation with rock strength. Rock brittleness also plays a role; when the rock is more brittle, the borehole shape is more complex. The formation contains abundant quartz and carbonates, which are brittle minerals. These minerals typically have high density. When drilling in shale, because the rock is softer and more brittle, the borehole shape and rock density are smaller. This algorithm is an empirical formula.

[0026] Preferably, the rock compressive strength involved in S6 is:

[0027]

[0028] Where φbulk is porosity, DCTbulk is rock fragment DTC, DCTma is typical sandstone DTC of the local sandstone strata, DCTw is water DTC of the local sandstone strata, and KCP is 0.6. Reference: Sandstone, Klein, Handbook of Fractured Petrophysics.

[0029] Preferably, the rock cuttings DTC is:

[0030]

[0031] Where UCS is the unrestricted rock compressive strength, DCTbulk is the obtained porosity, and A is the lithology code. A is a code, and the lithology code for sandstone is 1.60.

[0032] The beneficial effects of this invention are as follows:

[0033] This invention overcomes the problems of wired tools being unable to operate or difficult to operate, and being costly, as well as the shortcomings and defects that wired tools may have when performing formation analysis. It provides an alternative based on surface cuttings analysis, with outputs comparable to downhole tools. The advantages of this method are lower deployment costs, safer operation, and lower risk to the borehole. Especially when dealing with unconventional formations, in addition to producing data similar to downhole wired tools, it also provides formation-related rock physical parameters and data, obtaining more elemental and mineral information than traditional wired elemental logging, further expanding the scope of mineral identification. Furthermore, due to the flexibility of the method, most XRF equipment can meet the requirements. Attached Figure Description

[0034] Figure 1 This is a simplified flowchart of the data acquisition method of the present invention. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] like Figure 1 As shown, this embodiment of the invention provides a method for acquiring downhole and surface logging data. The steps of this data acquisition method are as follows:

[0037] S1, Preparatory work; Based on geological exploration data and the geological structure of the target area, determine the drilling location, drilling depth, and drilling type for downhole operations;

[0038] S2, Obtaining or collecting cuttings; cuttings can be obtained or collected at the surface location during drilling operations, through the drilling fluid circulated by the drilling pump during the drilling process.

[0039] S3, rock cuttings sample analysis; rock cuttings sample analysis is performed using a single XRF-based surface tool (X-ray fluorescence) or a combination of XRF and XRD-based surface tools (X-ray diffraction), producing two sets of rock cuttings analysis data;

[0040] S4 generates downhole wired data; downhole wired data is generated by simulating the cuttings analysis data obtained in S2.

[0041] Compared to wired datasets obtained through traditional methods, these datasets can be directly and accurately correlated with depth, providing additional comparability and feasibility.

[0042] S5, Data Processing: Process the generated raw data, such as filtering, denoising, and correction, to obtain well logging curves that can be used for analysis;

[0043] S6, Data Calculation: Use the data obtained above as different inputs into the formula, and obtain the corresponding output as the result based on the input;

[0044] S7, Analyze the results to obtain data; analyze the obtained data and acquire downhole operation and surface logging data.

[0045] Specifically, the rock fragmentation analysis data in S3 is an elemental or mineral dataset. The physical data of these rock fragments are obtained based on the elemental or mineral datasets of XRF and XRD data, including: density, rock strength, and sound wave propagation time.

[0046] The surface-based rock cuttings analysis disclosed herein can provide rock physical data, including but not limited to unrestricted rock compressive strength, rock density, rock cuttings gamma, time to sound propagation (DTC), organic matter concentration (TOC index), brittleness index, mobile hydrocarbon index, wellbore caliper index, porosity, and permeability.

[0047] The formula used in S6 is: ((Mineral A * coefficient + Mineral B * coefficient + ...) * adjustment coefficient) / adjustment coefficient;

[0048] Specifically

[0049] Wherein GR represents the gamma output of the cuttings, U% is the percentage of uranium in the sample, Ur is the elemental radiation of uranium in the sample, Th% is the percentage of thorium in the sample, Thr is the elemental radiation of thorium in the sample, K% is the percentage of potassium in the sample, and Kr is the elemental radiation of potassium in the sample; furthermore, in the equation, A, B, and C are coefficients used to determine the gamma values ​​from the cuttings data; coefficients A, B, and C can be obtained from the correlation of the core data.

[0050] From the first output (element output), a third output can be calculated. The third output is a cuttings gamma ray. The third output of the cuttings gamma ray can receive specific elemental data (e.g., uranium, potassium, and thorium) as input. The gamma ray output can be used to correct the well depth of all other data, thus ensuring a surface-based depth-related data analysis.

[0051] The TOC index can be obtained through the following relationship:

[0052]

[0053] GRLWD is the gamma output based on the drilling data during logging, while GR cuttings gamma is the gamma output from the third output. In some cases, when GRLWD may be equal to or less than GR cuttings gamma, for example, when GRLWD shows an invalid value measured by a wired tool, then the default value of "0" can be assumed. The comparison condition "IF" in the model can control the validity of the results.

[0054] The third output, cuttings gamma, can be used to calculate the fourth output. The fourth output is a measurement of mobile hydrocarbons (TOC index) based on cuttings. In addition to receiving gamma data outputs, the determination of the fourth output may also include logging-time gamma data. Cuttings gamma is always less than LWD gamma; the difference is that cuttings samples are dry and free of mobile organic matter upon washing, while LWD gamma is a volumetric (total) gamma.

[0055] The third output (gamma output), the second output (mineralogical output), and borehole inputs are used for quality control and evaluation. Drilling inputs may include drilling logging gamma information, penetration rate information, torque information, pumping rate information, etc. (i.e., data and information directly related to drilling operations and / or downhole data). Quality control may determine the validity of data samples based on downhole information and / or correlate these outputs (first, second, third, and fourth outputs) with depth and / or depth intervals.

[0056] However, if the data is determined to be sufficient and accurate, a fifth output of rock cutting density can be generated.

[0057] The density of the rock fragment mineral matrix involved in S6 is as follows:

[0058]

[0059] Where ρcutting is the mineral matrix density of the rock fragments, M1 is the amount of the first mineral in the sample, ρ1 is the density of the first mineral, M2 is the amount of the second mineral in the sample, ρ2 is the density of the second mineral, M3 is the amount of the third mineral in the sample, ρ3 is the density of the third mineral, Mn is the amount of the nth mineral in the sample, and ρn is the density of the nth mineral. In the formula, the coefficient or constant 'a' is a constant from 0 to 1, representing a missing material, while the density from the core is 100%, which is estimated based on local experience of the formation. Shale is heavier than sandstone because rock material is more easily lost when collecting shale rock fragment samples with a mud collector. The constant A can also be determined in another way from core data and lithology. Typically, when using a mud collector, some material and / or minerals may be missed during the preparation of rock fragment samples (through washing and grinding), but using the constant A in the formula can yield more accurate results for the mineral matrix density of the rock fragments.

[0060] The fifth output (density) can be combined with mineralogical and acoustic data to generate a sixth output. The sixth output is the cutter-based acoustic transmission velocity (DTC). The cutter-based quantity DTC is a pseudo-value, taking density as input, meaning that some material and / or minerals may be missed during the preparation of the cut sample, resulting in a pseudo-value for the DTC. It represents the baseline level of the DTC measured from the cutter. It must then be recalibrated by a local kernel. Mineralogical data can be a second input and can be obtained using core (e.g., downhole) and / or laboratory-based data. Acoustic data can be compressed acoustic data from a cross-dipole wire log. Therefore, downhole drilling data can be combined with the surface-based drill cuttings data of this disclosure to generate additional outputs indicating downhole formation characteristics and properties.

[0061] The relationship between the rock fragment mineral matrix density and the DTC from the cross dipole pair involved in S6 is as follows:

[0062] DTC 岩屑 =1*(1-DTC) index2 )*ρ cutting *DTC index3 +DTC index1

[0063] Where DCTbulk is the volumetric DCT, ρcutting is the fifth output mineral matrix density of cuttings (calibrated with core), and DCTindex1, DCTindex3, and DCTindex4 can be derived from the cross-dipole logarithmic correlation model. The density can also be obtained from cross-dipole wired logging. Then, the relationship between density and DTC is established using cross-dipole wired logging. A DTC algorithm can be established using cross-dipole wired logging. Based on the mineral density as input to this algorithm, DTC can be generated. The mineral matrix DTC is a pseudo-value and must be calibrated using cores.

[0064] Furthermore, the fifth output (density) and the second output (mineralogical output) can be used to generate the seventh output. The seventh output is a caliper index. The caliper index (seventh output) can be based on mineralogical density and brittleness. Caliper is closely related to density and brittleness.

[0065] The well diameter involved in S6 is:

[0066]

[0067] Where Cindex is the borehole diameter index, ρcutting is the density of the cuttings mineral matrix, and B represents brittleness. The borehole diameter index, as an indicator of borehole shape, represents the original borehole shape without reaming or reaming. Drilling operations such as reaming and reaming may alter the original shape. The borehole diameter here conforms to the original borehole shape. The borehole shape is determined by the rock strength; the harder the rock, the more complete the borehole shape. Density plays a significant role in rock strength, having a positive correlation with rock strength. Rock brittleness also plays a role; when the rock is more brittle, the borehole shape is more complex. Formations rich in quartz and carbonates are brittle minerals, typically with high density. When drilling in shale, due to the softer and more brittle rock, the borehole shape and rock density are smaller. This algorithm is an empirical formula.

[0068] The rock compressive strength involved in S6 is:

[0069]

[0070] Where φbulk is porosity, DCTbulk is rock fragment DTC, DCTma is typical sandstone DTC of the local sandstone strata, DCTw is water DTC of the local sandstone strata, and KCP is 0.6. Reference: Sandstone, Klein, etc., Handbook of Fractured Petrophysics.

[0071] Wherein, the rock cuttings DTC is:

[0072]

[0073] Where UCS is the unrestricted rock compressive strength, DCTbulk is the obtained porosity, and A is the lithology code. A is a code, and the lithology code for sandstone is 1.60.

[0074] Based on cuttings analysis using XRF and / or XRD, up to nine different formation rock properties can be extracted. Therefore, embodiments of this disclosure target broad-spectrum analysis of rock properties based on basic real-time analysis of a single cuttings sample returned to the surface during drilling operations. No additional downhole tools are required, except to potentially validate and / or improve data accuracy. Furthermore, multiple separate samples are not required, thus enabling a relatively fast and secure mechanism for reliably generating petrographic data. In other words, embodiments of this disclosure are capable of extracting downhole rock properties from cuttings analysis on a broad scale, rather than relying on downhole analyses (e.g., core samples, downhole cable tools, etc.).

[0075] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0076] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for acquiring downhole and surface logging data, characterized in that: The steps for obtaining this data are as follows: S1, Preparatory work; Based on geological exploration data and the geological structure of the target area, determine the drilling location, drilling depth, and drilling type for downhole operations; S2, Obtaining or collecting cuttings; cuttings can be obtained or collected at the surface location during drilling operations, through the drilling fluid circulated by the drilling pump during the drilling process. S3, Cuttings Sample Analysis; Cuttings sample analysis is performed using a single XRF-based surface tool or a combination of XRF and XRD-based surface tools, producing two sets of cuttings analysis data; S4 generates downhole wired data; The cuttings analysis data obtained from S2 was used to simulate and generate downhole wired data. S5, Data Processing: Process the generated raw data, such as filtering, denoising, and correction, to obtain well logging curves that can be used for analysis; S6, Data Calculation: Use the data obtained above as different inputs into the formula, and obtain the corresponding output as the result based on the input; S7, Analyze the results to obtain data; The obtained data is analyzed to acquire downhole operation and surface logging data.

2. The method for acquiring downhole and surface logging data according to claim 1, characterized in that: The rock fragmentation analysis data in S3 is specifically an elemental or mineral dataset. The physical data of these rock fragments are obtained based on the elemental or mineral datasets of XRF and XRD data, specifically including: density, rock strength, and sound wave propagation time.

3. The method for acquiring downhole and surface logging data according to claim 1, characterized in that: The formula used in S6 is: ((Mineral A * coefficient + Mineral B * coefficient + ...) * adjustment coefficient) / adjustment coefficient; Specifically, GR Where GR is the gamma output of the cuttings, U% is the percentage of uranium in the sample, Ur is the elemental radiation of uranium in the sample, Th% is the percentage of thorium in the sample, Thr is the elemental radiation of thorium in the sample, K% is the percentage of potassium in the sample, and Kr is the elemental radiation of potassium in the sample; in addition, A, B, and C are coefficients used to determine the gamma value from the cuttings data in the equation. Coefficients A, B, and C are derived from the correlation of the core data.

4. The method for acquiring downhole operation and surface logging data according to claim 1, characterized in that: The mineral matrix density of the rock fragments involved in S6 is: Where ρcutting is the density of the rock fragment mineral matrix, M1 is the amount of the first mineral in the sample, ρ1 is the density of the first mineral, M2 is the amount of the second mineral in the sample, ρ2 is the density of the second mineral, M3 is the amount of the third mineral in the sample, ρ3 is the density of the third mineral, Mn is the amount of the nth mineral in the sample, and ρn is the density of the nth mineral.

5. The method for acquiring downhole operation and surface logging data according to claim 1, characterized in that: The relationship between the rock fragment mineral matrix density and the DTC from the cross-dipole pair number involved in S6 is as follows: DTC 岩屑 =1*(1-DTC index2 )*ρ cutting *DTC index3 +DTC index1 Where DCTbulk is the volumetric DCT, ρcutting is the fifth output mineral matrix density of cuttings (calibrated with core), DCTindex1, DCTindex3 and DCTindex4 can be obtained from the cross-dipole logarithmic correlation model, and the density is also obtained from the cross-dipole wired logging. Then, the relationship between density and DTC is established using the cross-dipole wired logarithmics, and the DTC algorithm is established using the cross-dipole wired logarithmics. Based on the density of minerals as the input of the algorithm, DTC is generated. The mineral matrix DTC is a pseudo-value and must be calibrated with cores.

6. The method for acquiring downhole and surface logging data according to claim 1, characterized in that: The well diameter involved in S6 is: Where Cindex is the borehole diameter index, ρcutting is the density of rock cuttings mineral matrix, and B is brittleness. The borehole diameter index, as an indicator of borehole shape, represents the original borehole shape without reaming or reaming. Reaming and reaming drilling operations may alter the original shape. Here, the borehole diameter conforms to the original borehole shape. The borehole shape is determined by the rock strength; the harder the rock, the more complete the borehole shape. Density plays an important role in rock strength, having a positive correlation with rock strength. Rock brittleness also plays a role; when the rock is more brittle, the borehole shape is more complex. The formation contains abundant quartz and carbonates, which are brittle minerals. These minerals typically have high density. When drilling in shale, because the rock is softer and more brittle, the borehole shape and rock density are smaller. This algorithm is an empirical formula.

7. The method for acquiring downhole and surface logging data according to claim 1, characterized in that: The rock compressive strength involved in S6 is: Where φbulk is porosity, DCTbulk is rock fragment DTC, DCTma is typical sandstone DTC of the local sandstone strata, DCTw is water DTC of the local sandstone strata, and KCP is 0.

6. Reference: Sandstone, Klein, Handbook of Fractured Petrophysics.

8. The method for acquiring downhole operation and surface logging data according to claim 1, characterized in that: The rock cuttings DTC is: Where UCS is the unrestricted rock compressive strength, DCTbulk is the obtained porosity, and A is the lithology code. A is a code, and the lithology code for sandstone is 1.60.

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